Abstract

Background and objective: Glucosamine is suggested to affect glucose transport and insulin resistance. The effects of oral glucosamine on serum glucose and insulin levels at the initiation and throughout the duration of a 3-h oral glucose tolerance test were examined.

Methods: Sera from 16 patients with osteoarthritis, but with no other diagnosed medical condition who had fasted overnight, were obtained every 15–30 min during the 3 h of continued fasting and during the 3 h after ingestion of 75 g of glucose with or without ingestion of 1500 mg of glucosamine sulphate. Glucose was analysed by high-performance liquid chromatography using a Metrohm-Peak 817 Bioscan, and the area under the curve (AUC) for glucose was calculated. Insulin was measured by radioimmunoassay every 30 min for 2 h.

Results: Three participants who were found to have previously undiagnosed abnormalities of glucose tolerance demonstrated significant (p = 0.04) incremental elevations in glucose levels after ingestion of glucosamine sulphate. The other 13 participants also had mean incremental elevations that were not significant (p = 0.20). Glucosamine sulphate ingestion had no effect on insulin levels.

Conclusion: The results suggest that glucosamine ingestion may affect glucose levels and consequent glucose uptake in patients who have untreated diabetes or glucose intolerance.